This invention relates to a weft cutting device for a loom, particularly adapted for use with a shuttleless, fluid weft injection type.
It is usual in this type of loom to sever the weft thread after each insertion into the shed, forming a selvage as the cloth is fabricated.
In one such known weft cutting device a thread cutter is fixed to and movable together with a reed frame. As the reed is moved forward for beating, the thread cutter is also moved toward the fell of cloth, whereat a suitable pressure applying member fixedly mounted on the loom frame urges the cutter blade to cut off the weft thread. This results in that the weft thread is cut off immediately before the occurrence of beating. Since the weft thread is not yet tightly grasped by the warp threads before beating, it is often skewed or tensioned in such a way during cutting that information of a neat, uniform and firm selvage is difficult.
Another known weft cutting device employs a thread cutter which is not directly fastened to the reed frame but is movable in relation with it to timely cut off the weft thread at the cloth fell. A device of this kind however has the disadvantage that the mechanism for moving the thread cutter separately from but in connection with the reed is undesirably complex.
It may also be pointed out that, particularly when a fabric of high density is woven, the weft thread is bounced back from the cloth fell during beating (so-called "bumping") and the position of the cutter is to be correspondingly adjusted in dependence on the amount of such "bumping".